Carbon dioxide results during the combustion of carbonaceous fuels. In a given energy source, the amount of carbon dioxide which is produced is directly dependent upon the amount of fuel and therefore upon the converted energy. Modern plants and operating methods can certainly utilize the energy contained in the fuel better than previously, but do not prevent the creation of the gas.
Since no effective and economical method is available for carbon dioxide separation, this amount escapes into the atmosphere and contributes towards global warming. In order to avoid carbon dioxide getting into the atmosphere, it is known to store carbon dioxide in chambers deep beneath the earth's surface. Thus, in the North Sea for years climate gas has been pumped into rock formations deep beneath the seabed.
For this purpose, carbon dioxide has to be brought from ambient pressure and temperature to a pressure level which allows introduction of the gas via pipelines into an underground deposit.
This means that a compressor unit for the carbon dioxide must deliver a discharge pressure of 80-300 bar.
For this purpose, a correspondingly large capacity is required.
From the “International Journal of Greenhouse Gas Control I (2007)”, an article by Audun Aspelund and Kristin Jordal was made known, which proposes CO2 compression below the critical pressure to about 65 bar and a subsequent cooling for the condensation with subsequent pumping to a discharge pressure of 150 bar.
Particularly the comparatively low closed cooling temperature of about 10° C., which especially at the warm time of the year is to be provided by natural heat sinks only with great difficulty or not at all, is disadvantageous to the described method. In this case, consideration is especially to be given to the fact the amounts of carbon dioxide which are to be compressed require the closed cooling of a huge compression plant.